1. Field of the Invention
The present invention relates to a component for a turbomachine having at least one region made of an intermetallic material, in particular a TiAl blade for a stationary gas turbine or an aircraft engine, and also to a process for producing such a component.
2. Discussion of Background Information
Intermetallic materials, such as titanium aluminides, which consist to a large extent of intermetallic phases are of interest for specific applications, for example in the construction of aircraft turbines, since, on account of their structure and their chemical bonds, they can have high strengths and at the same time, on account of a low specific weight, can form components having a low weight, as is the case in particular with materials based on titanium aluminides (TiAl materials).
However, for use in stationary gas turbines or aircraft engines, the TiAl materials in certain applications require additional surface modification in order to fulfill all the requirements.
Thus, it is known, for example, to solder on small plates made of a wear-resistant alloy, for example the alloy Tribaloy T800 (trade name of Deloro Stellite Holdings Corporation), in the region of the contact surfaces of shrouds of adjacent blades, what is termed the z notch, in the case of TiAl blades of gas turbines, in order to reduce the wear.
However, intermetallic materials and correspondingly also TiAl blades are difficult to solder, and therefore the soldered joint with the T800 small plates which have been soldered on often does not satisfy the requirements.
Moreover, it may also be necessary to modify the surface in other regions of TiAl blades, in order for example to avoid the formation of cracks, as can form for example in the region of the blade roots at the contact points with the disk groove of a rotor disk or during the impingement of particles on the main blade part.
In view of the foregoing, it would be advantageous to provide surface modification for components based on intermetallic materials, such that firstly the connection to other components, for example wear-resistant plates, is improved and secondly the surface generally becomes less sensitive to the formation of cracks. It would also be advantageous if a a corresponding surface modification could be made easily and reliably.